Human-powered paddlewheel boats are well known for recreational use and have been available in a number of different forms over the years.
Portability, maneuverability and speed are design factors which are often contrary. The prior art has not been entirely successful in achieving all of the above factors in combination.
As early as 1938, in U.S. Pat. No. 2,253,936 to Karst, hand-cranked paddlewheels were positioned either side of a floating craft which was capable of seating several persons, positioned about game boards, such as a checker board. Three floats, such as toroidal inflatable tubes, are placed in a line and secured together with two long peripheral beams. Having a function like oars, paddlewheels are positioned amidships on each side of the craft. Each paddlewheel rotational shaft is fixed to hand cranks. While the craft appears stable, due in part to its length, it is unlikely very maneuverable, and having floats which extend transverse to the direction of movement makes it unlikely to be particularly swift.
In U.S. Pat. No. 5,183,422 to Guiboche, the maneuverability issue is addressed by providing a single toroidal inflatable tube float. The operator sits atop a platform secured to the tube. Two independently driven paddlewheels are positioned within the inner radius of the float and below the platform. Pedals are mounted on S-shaped axles. The axle's ends terminate above the two paddlewheels and belt drives drive the paddlewheels. Two levers, operated by the operators left and right hands actuate engagement and disengagement of the pedal drive and paddlewheels for enabling steering. Engagement is through axially engaging and disengaging a splined shaft within the splined bore of the paddlewheel. Spring-biasing maintains the drives engaged state. By selectively driving only one of the two paddlewheels, turns can be made. While the ability to turn is likely very good, forward movement is again impeded by the use of the toroidal tube float.
Another desirable feature is the ability to easily transport the boat to a recreation site. This ability is addressed in part in U.S. Pat. No. 5,174,232 to Boddy. Boddy discloses an inflatable catamaran having a substantially three part planer frame which assembles to lie across the linearly elongate inflatable tubes forming two hulls. The frame forms a platform on a catamaran for powering by sail, motor or oars. This design, while it allows the frame to be tri-folded, with or without the hulls attached, positions the operator at the hull level, and does not integrate pedal drive means into the frame.
The boat of Karst is not realistically collapsible for transport. The paddle boat of Guiboche does not contemplate portability other than describing the disassembly and re-assembly of the platform into four separate sections. Further, the drive arrangement of Guiboche is constrained to be at least as wide as the S-shape axle when disassembled, which extends transversely and fully to the paddlewheels.
Accordingly, there is a yet a human-powered, pedal-driven boat which satisfies the criteria of utilizing an efficient streamlined hull arrangement, providing great maneuverability and enabling luggable portability for transport.